土壤盐分变化对N_(2)O排放影响:基于Meta分析

Effect of Different Soil Salinities on N2O Emission:A Meta-analysis

N_(2)O是导致臭氧层空洞和全球变暖的主要大气污染物,农业生产活动是其主要来源,而土壤盐分则是影响N_(2)O排放的关键因素.基于21篇同行评议文献中528对实验组及对照组形成的数据集,运用R语言Metafor软件包进行Meta分析,进而评估土壤盐分对土壤N_(2)O排放的影响.结果表明,土壤盐分累积对N_(2)O排放量有显著正效应,中度和高度盐渍土N_(2)O排放量比非盐渍土高75.57%和28.85%.室内培养实验测定结果表明,林地和农田的土壤盐渍化导致N_(2)O排放量增加124.79%和131.64%,而野外定位监测试验结果表明,草地、裸地和农田中,土壤盐分对N_(2)O排放的影响均不显著.盐分对N_(2)O排放的影响趋势则因土壤(NH_(4)^(+)∶NO_(3)^(-))、p H、土壤砂粒含量和粉粒含量的差异而发生改变,影响程度依次是:(NH_(4)^(+)∶NO_(3)^(-))>p H>砂粒含量>粉粒含量.通过揭示土壤盐分升高对不同土地利用类型下N_(2)O排放的刺激作用,明确了环境因子和盐分交互作用对N_(2)O排放的影响,对土壤盐渍化地区N_(2)O排放预防阻控和环境改善具有重要科学意义.

N2O is the main air pollutant that causes the ozonosphere hole and global warming.Agricultural production activities are the cause of soil N2O production,and soil salinity is the key factor affecting N2O emissions.In order to evaluate the effect of soil salinity on N2O emissions,we used the Metafor software package of R language to analyze the data sets formed by 528 pairs of experimental and control groups in 21 peer-reviewed literatures.The results showed that soil salt accumulation had a significant positive effect on N2O emissions.The N2O emissions of moderately and highly salinized soils were 75.57%and 28.85%higher than those of non-saline soils,respectively.The results of laboratory experiments showed that salt had no significant effect on N2O emissions in grassland and bare land,whereas for forest land and farmland soil,soil salinization led to an increase in N2O emissions of 124.79%and 131.64%,respectively.However,the results of field experiments showed that the influence of soil salinity on N2O emissions was not significant in grassland,bare land,and farmland.The influence trend of salinity on N2O emission was changed by the difference in soil(NH_(4)^(+)∶NOO_(3)^(-)),pH,soil sand content,and silt content.The degree of influence of environmental factors on N2O emission was(NH_(4)^(+)∶NOO_(3)^(-))>pH>sand content>silt content.Our research revealed the stimulating effect of increasing soil salinity on N2O emissions from different land use types.We identified the interaction of environmental factors and salinity on N2O emissions.This article has important scientific significance for reducing N2O emissions in salinized land soil and improving the environment.